Existing portable locking devices, such as padlocks, are generally limited to operation with a shackle that is permanently connected at one end to the lock body, or with one specific type of shackle element. Existing cables and cable-like shackle assemblies are equipped with only rudimentary sensors for monitoring and detecting the condition of the cable. Padlocks with wireless capability typically report condition using a simple, binary message (for example, Lock OK or Lock Not OK) and lack the capacity to transmit or receive signals in remote areas.
Thus, there is need in the art for improved portable locking devices.